Mazda Mazda6 Workshop Manual Supplement page 297

DTC P0504
DTC P0504 Brake switch signal correlation malfunction
• PCM monitors input signal from brake switch 1 and brake switch 2 while engine is running. PCM
determines brake switch signal correlation malfunction if input signal from brake switch 1 brake switch 2 is
DETECTION
as following:
CONDITION
— Brake switch 1 is ON and brake switch 2 is ON.
— Brake switch 1 is OFF and brake switch 2 is OFF.
• Brake switch malfunction
• Connector or terminal malfunction
• Open circuit in wiring between main fuse and brake switch terminal B
• Open circuit in wiring between brake switch terminal D and PCM terminal 7
POSSIBLE
• Short to power circuit in wiring between brake switch terminal D and PCM terminal 7
CAUSE
• Open circuit in wiring between brake switch terminal C and GND
• Short to GND in wiring between brake switch terminal A and PCM terminal 34
• Open circuit in wiring between brake switch terminal A and PCM terminal 34
• PCM malfunction
MAIN FUSE
4
10
16 15
HARNESS SIDE CONNECTOR
Diagnostic procedure
STEP
1 VERIFY RELATED REPAIR INFORMATION
AVAILABILITY
• Check for related Service Information
availability.
• Is any related repair information available?
2 CLASSIFY MALFUNCTION OF BRAKE SWITCH
1 OR BRAKE SWITCH 2
• Turn engine switch to ON (Engine OFF).
• Access BOO PID using WDS or equivalent.
• Verify that BOO PID is changed according to
brake pedal condition.
(See F2–65 PCM
• Is BOO PID okay?
3 CLASSIFY HIGH INPUT OR LOW INPUT
• Turn engine switch to ON (Engine OFF).
• Access BOO PID using WDS or equivalent.
• Verify BOO PID during brake pedal operation.
• Is BOO PID always OFF?
ON-BOARD DIAGNOSTIC
BRAKE SWITCH
4
10
B D
6 12
17
15
A
C
BRAKE SWITCH
C A
D B
INSPECTION
INSPECTION)
8
9 13
14
7
18 19
34
HARNESS SIDE CONNECTOR
Yes Perform repair or diagnosis according to available Service
Information.
• If vehicle is not repaired, go to next step.
No Go to next step.
Yes Go to Step 15.
No Go to next step.
Yes Go to next step.
No Go to Step 10.
A6E407001082234
PCM
PCM
34
7
ACTION
F2–145
F2